***/
#include <errno.h>
+#include <limits.h>
+#include <sys/mount.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/epoll.h>
+#include <sys/stat.h>
+#include <linux/auto_fs4.h>
+#include <linux/auto_dev-ioctl.h>
#include "unit.h"
#include "automount.h"
#include "load-fragment.h"
#include "load-dropin.h"
+#include "unit-name.h"
static const UnitActiveState state_translation_table[_AUTOMOUNT_STATE_MAX] = {
[AUTOMOUNT_DEAD] = UNIT_INACTIVE,
[AUTOMOUNT_MAINTAINANCE] = "maintainance"
};
+static char *automount_name_from_where(const char *where) {
+ assert(where);
+
+ if (streq(where, "/"))
+ return strdup("-.automount");
+
+ return unit_name_build_escape(where+1, NULL, ".automount");
+}
+
static void automount_init(Unit *u) {
Automount *a = AUTOMOUNT(u);
- a->state = 0;
+ assert(u);
+ assert(u->meta.load_state == UNIT_STUB);
+
+ a->pipe_watch.fd = a->pipe_fd = -1;
+}
+
+static void repeat_unmout(const char *path) {
+ assert(path);
+
+ for (;;) {
+
+ if (umount2(path, MNT_DETACH) >= 0)
+ continue;
+
+ if (errno != EINVAL)
+ log_error("Failed to unmount: %m");
+
+ break;
+ }
+}
+
+static void unmount_autofs(Automount *a) {
+ assert(a);
+
+ if (a->pipe_fd < 0)
+ return;
+
+ automount_send_ready(a, -EHOSTDOWN);
+
+ unit_unwatch_fd(UNIT(a), &a->pipe_watch);
+ close_nointr_nofail(a->pipe_fd);
+ a->pipe_fd = -1;
+
+ repeat_unmout(a->where);
+}
+
+static void automount_done(Unit *u) {
+ Automount *a = AUTOMOUNT(u);
+
+ assert(a);
+
+ unmount_autofs(a);
a->mount = NULL;
+
+ if (a->tokens) {
+ set_free(a->tokens);
+ a->tokens = NULL;
+ }
+}
+
+static int automount_verify(Automount *a) {
+ bool b;
+ char *e;
+ assert(a);
+
+ if (UNIT(a)->meta.load_state != UNIT_LOADED)
+ return 0;
+
+ if (!a->where) {
+ log_error("%s lacks Where setting. Refusing.", UNIT(a)->meta.id);
+ return -EINVAL;
+ }
+
+ path_kill_slashes(a->where);
+
+ if (!(e = automount_name_from_where(a->where)))
+ return -ENOMEM;
+
+ b = unit_has_name(UNIT(a), e);
+ free(e);
+
+ if (!b) {
+ log_error("%s's Where setting doesn't match unit name. Refusing.", UNIT(a)->meta.id);
+ return -EINVAL;
+ }
+
+ return 0;
}
static int automount_load(Unit *u) {
return r;
}
- return 0;
+ return automount_verify(a);
}
-static void automount_done(Unit *u) {
- Automount *a = AUTOMOUNT(u);
-
+static void automount_set_state(Automount *a, AutomountState state) {
+ AutomountState old_state;
assert(a);
- a->mount = NULL;
+ old_state = a->state;
+ a->state = state;
+
+ if (state != AUTOMOUNT_WAITING &&
+ state != AUTOMOUNT_RUNNING)
+ unmount_autofs(a);
+
+ if (state != old_state)
+ log_debug("%s changed %s → %s", UNIT(a)->meta.id, state_string_table[old_state], state_string_table[state]);
+
+ unit_notify(UNIT(a), state_translation_table[old_state], state_translation_table[state]);
}
static void automount_dump(Unit *u, FILE *f, const char *prefix) {
prefix, state_string_table[s->state]);
}
+static void automount_enter_dead(Automount *a, bool success) {
+ assert(a);
+
+ if (!success)
+ a->failure = true;
+
+ automount_set_state(a, a->failure ? AUTOMOUNT_MAINTAINANCE : AUTOMOUNT_DEAD);
+}
+
+static int open_dev_autofs(Manager *m) {
+ struct autofs_dev_ioctl param;
+
+ assert(m);
+
+ if (m->dev_autofs_fd >= 0)
+ return m->dev_autofs_fd;
+
+ if ((m->dev_autofs_fd = open("/dev/autofs", O_RDONLY)) < 0) {
+ log_error("Failed to open /dev/autofs: %s", strerror(errno));
+ return -errno;
+ }
+
+ init_autofs_dev_ioctl(¶m);
+ if (ioctl(m->dev_autofs_fd, AUTOFS_DEV_IOCTL_VERSION, ¶m) < 0) {
+ close_nointr_nofail(m->dev_autofs_fd);
+ m->dev_autofs_fd = -1;
+ return -errno;
+ }
+
+ log_debug("Autofs kernel version %i.%i", param.ver_major, param.ver_minor);
+
+ return m->dev_autofs_fd;
+}
+
+static int open_ioctl_fd(int dev_autofs_fd, const char *where, dev_t devid) {
+ struct autofs_dev_ioctl *param;
+ size_t l;
+ int r;
+
+ assert(dev_autofs_fd >= 0);
+ assert(where);
+
+ l = sizeof(struct autofs_dev_ioctl) + strlen(where) + 1;
+
+ if (!(param = malloc(l)))
+ return -ENOMEM;
+
+ init_autofs_dev_ioctl(param);
+ param->size = l;
+ param->ioctlfd = -1;
+ param->openmount.devid = devid;
+ strcpy(param->path, where);
+
+ if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_OPENMOUNT, param) < 0) {
+ r = -errno;
+ goto finish;
+ }
+
+ if (param->ioctlfd < 0) {
+ r = -EIO;
+ goto finish;
+ }
+
+ r = param->ioctlfd;
+
+finish:
+ free(param);
+ return r;
+}
+
+static int autofs_protocol(int dev_autofs_fd, int ioctl_fd) {
+ uint32_t major, minor;
+ struct autofs_dev_ioctl param;
+
+ assert(dev_autofs_fd >= 0);
+ assert(ioctl_fd >= 0);
+
+ init_autofs_dev_ioctl(¶m);
+ param.ioctlfd = ioctl_fd;
+
+ if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_PROTOVER, ¶m) < 0)
+ return -errno;
+
+ major = param.protover.version;
+
+ init_autofs_dev_ioctl(¶m);
+ param.ioctlfd = ioctl_fd;
+
+ if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_PROTOSUBVER, ¶m) < 0)
+ return -errno;
+
+ minor = param.protosubver.sub_version;
+
+ log_debug("Autofs protocol version %i.%i", major, minor);
+ return 0;
+}
+
+static int autofs_set_timeout(int dev_autofs_fd, int ioctl_fd, time_t sec) {
+ struct autofs_dev_ioctl param;
+
+ assert(dev_autofs_fd >= 0);
+ assert(ioctl_fd >= 0);
+
+ init_autofs_dev_ioctl(¶m);
+ param.ioctlfd = ioctl_fd;
+ param.timeout.timeout = sec;
+
+ if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_TIMEOUT, ¶m) < 0)
+ return -errno;
+
+ return 0;
+}
+
+static int autofs_send_ready(int dev_autofs_fd, int ioctl_fd, uint32_t token, int status) {
+ struct autofs_dev_ioctl param;
+
+ assert(dev_autofs_fd >= 0);
+ assert(ioctl_fd >= 0);
+
+ init_autofs_dev_ioctl(¶m);
+ param.ioctlfd = ioctl_fd;
+
+ if (status) {
+ param.fail.token = token;
+ param.fail.status = status;
+ } else
+ param.ready.token = token;
+
+ if (ioctl(dev_autofs_fd, status ? AUTOFS_DEV_IOCTL_FAIL : AUTOFS_DEV_IOCTL_READY, ¶m) < 0)
+ return -errno;
+
+ return 0;
+}
+
+int automount_send_ready(Automount *a, int status) {
+ int ioctl_fd, r;
+ unsigned token;
+
+ assert(a);
+ assert(status <= 0);
+
+ if (set_isempty(a->tokens))
+ return 0;
+
+ if ((ioctl_fd = open_ioctl_fd(UNIT(a)->meta.manager->dev_autofs_fd, a->where, a->dev_id)) < 0) {
+ r = ioctl_fd;
+ goto fail;
+ }
+
+ if (status)
+ log_debug("Sending failure: %s", strerror(-status));
+ else
+ log_debug("Sending success.");
+
+ /* Autofs thankfully does not hand out 0 as a token */
+ while ((token = PTR_TO_UINT(set_steal_first(a->tokens)))) {
+ int k;
+
+ /* Autofs fun fact II:
+ *
+ * if you pass a positive status code here, the kernel will
+ * freeze! Yay! */
+
+ if ((k = autofs_send_ready(UNIT(a)->meta.manager->dev_autofs_fd,
+ ioctl_fd,
+ token,
+ status)) < 0)
+ r = k;
+ }
+
+ r = 0;
+
+fail:
+ if (ioctl_fd >= 0)
+ close_nointr_nofail(ioctl_fd);
+
+ return r;
+}
+
+static void automount_enter_waiting(Automount *a) {
+ int p[2] = { -1, -1 };
+ char name[32], options[128];
+ bool mounted = false;
+ int r, ioctl_fd = -1, dev_autofs_fd;
+ struct stat st;
+
+ assert(a);
+ assert(a->pipe_fd < 0);
+ assert(a->where);
+
+ if (a->tokens)
+ set_clear(a->tokens);
+ else if (!(a->tokens = set_new(trivial_hash_func, trivial_compare_func))) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ if ((dev_autofs_fd = open_dev_autofs(UNIT(a)->meta.manager)) < 0) {
+ r = dev_autofs_fd;
+ goto fail;
+ }
+
+ /* We knowingly ignore the results of this call */
+ mkdir_p(a->where, 0555);
+
+ if (pipe2(p, O_NONBLOCK) < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ snprintf(options, sizeof(options), "fd=%i,pgrp=%u,minproto=5,maxproto=5,direct", p[1], (unsigned) getpgrp());
+ char_array_0(options);
+
+ snprintf(name, sizeof(name), "systemd-%u", (unsigned) getpid());
+ char_array_0(name);
+
+ if (mount(name, a->where, "autofs", 0, options) < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ mounted = true;
+
+ close_nointr_nofail(p[1]);
+ p[1] = -1;
+
+ if (stat(a->where, &st) < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ if ((ioctl_fd = open_ioctl_fd(dev_autofs_fd, a->where, st.st_dev)) < 0) {
+ r = ioctl_fd;
+ goto fail;
+ }
+
+ if ((r = autofs_protocol(dev_autofs_fd, ioctl_fd)) < 0)
+ goto fail;
+
+ if ((r = autofs_set_timeout(dev_autofs_fd, ioctl_fd, 300)) < 0)
+ goto fail;
+
+ /* Autofs fun fact:
+ *
+ * Unless we close the ioctl fd here, for some weird reason
+ * the direct mount will not receive events from the
+ * kernel. */
+
+ close_nointr_nofail(ioctl_fd);
+ ioctl_fd = -1;
+
+ if ((r = unit_watch_fd(UNIT(a), p[0], EPOLLIN, &a->pipe_watch)) < 0)
+ goto fail;
+
+ a->pipe_fd = p[0];
+ a->dev_id = st.st_dev;
+
+ automount_set_state(a, AUTOMOUNT_WAITING);
+
+ return;
+
+fail:
+ assert_se(close_pipe(p) == 0);
+
+ if (ioctl_fd >= 0)
+ close_nointr_nofail(ioctl_fd);
+
+ if (mounted)
+ repeat_unmout(a->where);
+
+ log_error("Failed to initialize automounter: %s", strerror(-r));
+ automount_enter_dead(a, false);
+}
+
+static void automount_enter_runnning(Automount *a) {
+ int r;
+ struct stat st;
+
+ assert(a);
+ assert(a->mount);
+
+ /* Before we do anything, let's see if somebody is playing games with us? */
+
+ if (stat(a->where, &st) < 0) {
+ log_warning("%s failed stat automount point: %m", a->meta.id);
+ goto fail;
+ }
+
+ if (!S_ISDIR(st.st_mode) || st.st_dev != a->dev_id)
+ log_info("%s's automount point already active?", a->meta.id);
+ else if ((r = manager_add_job(UNIT(a)->meta.manager, JOB_START, UNIT(a->mount), JOB_REPLACE, true, NULL)) < 0) {
+ log_warning("%s failed to queue mount startup job: %s", a->meta.id, strerror(-r));
+ goto fail;
+ }
+
+ automount_set_state(a, AUTOMOUNT_RUNNING);
+ return;
+
+fail:
+ automount_enter_dead(a, false);
+}
+
+static int automount_start(Unit *u) {
+ Automount *a = AUTOMOUNT(u);
+
+ assert(a);
+
+ if (path_is_mount_point(a->where)) {
+ log_error("Path %s is already a mount point, refusing start for %s", a->where, u->meta.id);
+ return -EEXIST;
+ }
+
+ assert(a->state == AUTOMOUNT_DEAD || a->state == AUTOMOUNT_MAINTAINANCE);
+
+ a->failure = false;
+ automount_enter_waiting(a);
+ return 0;
+}
+
+static int automount_stop(Unit *u) {
+ Automount *a = AUTOMOUNT(u);
+
+ assert(a);
+
+ assert(a->state == AUTOMOUNT_WAITING || a->state == AUTOMOUNT_RUNNING);
+
+ automount_enter_dead(a, true);
+ return 0;
+}
+
static UnitActiveState automount_active_state(Unit *u) {
return state_translation_table[AUTOMOUNT(u)->state];
return state_string_table[AUTOMOUNT(u)->state];
}
+static void automount_fd_event(Unit *u, int fd, uint32_t events, Watch *w) {
+ union autofs_v5_packet_union packet;
+ ssize_t l;
+ int r;
+
+ Automount *a = AUTOMOUNT(u);
+
+ assert(a);
+ assert(fd == a->pipe_fd);
+
+ if (events != EPOLLIN) {
+ log_error("Got invalid poll event on pipe.");
+ goto fail;
+ }
+
+ if ((l = loop_read(a->pipe_fd, &packet, sizeof(packet))) != sizeof(packet)) {
+ log_error("Invalid read from pipe: %s", l < 0 ? strerror(-l) : "short read");
+ goto fail;
+ }
+
+ switch (packet.hdr.type) {
+
+ case autofs_ptype_missing_direct:
+ log_debug("Got direct mount request for %s", packet.v5_packet.name);
+
+ if ((r = set_put(a->tokens, UINT_TO_PTR(packet.v5_packet.wait_queue_token))) < 0) {
+ log_error("Failed to remember token: %s", strerror(-r));
+ goto fail;
+ }
+
+ automount_enter_runnning(a);
+ break;
+
+ default:
+ log_error("Received unknown automount request %i", packet.hdr.type);
+ break;
+ }
+
+ return;
+
+fail:
+ automount_enter_dead(a, false);
+}
+
+static void automount_shutdown(Manager *m) {
+ assert(m);
+
+ if (m->dev_autofs_fd >= 0)
+ close_nointr_nofail(m->dev_autofs_fd);
+}
+
const UnitVTable automount_vtable = {
- .suffix = ".mount",
+ .suffix = ".automount",
.no_alias = true,
+ .no_instances = true,
.init = automount_init,
.load = automount_load,
.dump = automount_dump,
+ .start = automount_start,
+ .stop = automount_stop,
+
.active_state = automount_active_state,
- .sub_state_to_string = automount_sub_state_to_string
+ .sub_state_to_string = automount_sub_state_to_string,
+
+ .fd_event = automount_fd_event,
+
+ .shutdown = automount_shutdown
};
~ianmdlvl / elogind.git / blobdiff